Almost any eyeglass frame in the prior art causes some kind of discomfort. Traditional eyeglass frames may cause soreness in area in which the eyeglasses rest on the bridge of the nose. Pain can be caused by weight on the sensitive portion of the ear from the earpieces on the ends of the frames temples. Besides the conventional eyeglass frames, goggles have been used which are attached by an elastic band. These goggles, however, may cause pain to the eye socket area due to the pressure caused by the use of the elastic band.
A second problem in the prior art relates to the positioning capabilities of the frame. Prior art frames often become repositioned because of activity. The proper position for a lens is directly over the pupil area of the eyes. Optically active lenses will not work as intended when out of position. Thus, the inadvertent repositioning of the prior art frames will cause blurred vision or other optical inadequacies.
A third problem in the prior art is that of frame fragility. Prior art frames are often easily broken. Most conventional frames have parts that can become loose and lead to involuntary disassembly. One example is the use of tiny screws which are used to attach the temples to the main part of the frame (where the lenses are). Another problem is with lenses popping out of their frame housings. Many artisans have attempted to overcome these deficiencies in the prior art with inadequate results. Temple pieces have been attached with spring-loaded screw elements to increase durability. However, these spring-loaded screws have caused discomfort because of the additional force they place on the temples. Though frames have been made more durable over the years, even the sturdiest of these prior art frames can be destroyed via mistreatment by a child or the inadvertent application of force thereto (i.e., users stepping or sitting on them).
A fourth problem with the prior art frames is that they tend to be insecure. Most conventional frames can be easily pulled off or even fall off accidentally, especially if the user is engaged some kind of athletic activity. Special frame retaining devices have been used to hold the frame more securely to the user's face. However, these types of retainers do not work with goggles or frames with cable earpieces. Additionally, when retainers are used along with traditional frames, they cause additional pressure on the nose, often driving the nose pads into the bridge of the nose, causing discomfort. Several artisans have endeavored to alleviate this pressure by alternatively supporting the lenses (e.g., U.S. Pat. No. 5,196,871). However, none of these prior art attempts have resulted in the complete relief of nose pressure.
A fifth problem with conventional frames, is what is known as “gapping.” Conventional frames hold the lenses out a distance from the face. This leaves a peripheral gap of uncorrected vision. In the case of sunglasses, gapping may leave the eye unprotected from various angles so that the eye is exposed to direct sunlight causing eye pain and possibly damage as a result. Some conventional sunglasses have addressed this problem by using frames that curve around and conform to the head (e.g., U.S. Pat. Nos. 5,576,775; 5,191,364; 5,189,447; and 4,741,611). However, none of these prior art designs adequately solves the peripheral vision problem—even in the case of goggles.
Another disadvantage of prior art frames is a kind of “greenhouse effect” caused by the sealed nature of prior art frames that are sealed to the skin, such as goggles. The stagnant air created by sealing the goggles to the face is heated by sunlight. This causes a buildup of heat. In addition to the heat and resulting sweat, another result is fog, which eliminates visibility. Unabsorbed sweat can cause irritation to the skin at the goggles' contact points. Aggravation of the situation can be caused by increased activity such as sports. Many artisans have strived to overcome these ventilation problems. (See for example, U.S. Pat. Nos. 5,867,841; 5,801,805; 6,065,833; 6,026,518; 5,722,035; 5,689,834; 5,576,775; 5,519,896; 5,239,320; and 6,216,282). However, need in the art still exists regarding these ventilation problems.
Prior art frames do not allow for easy removal of and replacement of lenses. Rather, most of the prior art lenses are integral to their respective frames. Many users desire a variety of lenses for different specific purposes. For example, some users will sometimes wear clear prescription lenses but then at a later time, desire lenses having a tint or some kind of UV protection. With the prior art lenses, these users would have to own a frame for each different kind of lens desired. However, most frames are expensive. Therefore, a need in the art exists to make a frame that allows for the interchangeability of a variety of lenses within a single frame.